- A combined experimental and theoretical investigation on the role of halide ligands on the catecholase-like activity of mononuclear nickel(II) complexes with a phenol-based tridentate ligand
-
Three new mononuclear nickel(II) complexes, namely, [NiL1(H 2O)3]I2·H2O (1), [NiL 1(H2O)3]Br2·H2O (2), and [NiL1(H2O)3
- Adhikary, Jaydeep,Chakraborty, Prateeti,Das, Sudhanshu,Chattopadhyay, Tanmay,Bauza, Antonio,Chattopadhyay, Shyamal Kumar,Ghosh, Bipinbihari,Mautner, Franz A.,Frontera, Antonio,Das, Debasis
-
-
Read Online
- Copper(II) complexes of piperazine based ligand: Synthesis, crystal structure, protein binding and evaluation of anti-cancerous therapeutic potential
-
The reaction of tridentate Schiff base {2-[(2-piperazine-1-yl-ethylimino)- methyl]-phenol} ligand (HOPhL) with copper(II) salts resulted three new compounds (i) [Cu(HNL)(NO3)(H2O)](NO 3) (1), (ii) [Cu
- Pait, Moumita,Kundu, Banani,Kundu, Subhas C.,Ray, Debashis
-
-
Read Online
- Synthesis, structure, DNA/protein binding, molecular docking and in vitro anticancer activity of two Schiff base coordinated copper(II) complexes
-
Two Schiff bases HL and HL′, having potential tridentate O,N,N′ donor sets, have been used for the synthesis of two copper(II) complexes, namely [Cu(HL)(pdc)]2 (1) and [Cu(L′)2]2 (2′), where HL = 2-([2-(piperazin-yl)ethyli
- Manna, Subal Chandra,Mistri, Soumen,Patra, Apu,Mahish, Manas Kumar,Saren, Dama,Manne, Rajesh Kumar,Santra, Manas Kumar,Zangrando,Puschmann
-
-
Read Online
- Portraying the role of halo ligands and the auxiliary part of ligands of mononuclear manganese(iii)-Schiff base complexes in catalyzing phospho-ester bond hydrolysis
-
Four mononucleating Schiff base ligands, namely HL1, HL2, HL3 and HL4, were prepared via condensation between 2-hydroxybenzaldehyde and 2-morpholinoethanamine, 2-(piperazin-1-yl)ethanamine, 2-(piperidin-1-yl)ethanamine and 2-(pyrrolidin-1-yl)ethanamine, r
- Chakraborty, Tonmoy,Dasgupta, Sanchari,Zangrando, Ennio,Das, Debasis
-
p. 14933 - 14942
(2018/09/29)
-
- Syntheses and characterization of monobasic tridentate Cu(II) Schiff-base complexes for efficient oxidation of 3,5-di-: tert -butylcatechol and oxidative bromination of organic substrates
-
Two monomeric copper complexes [CuII(sal-ppzH)Cl2] (1) and [CuII(hyap-ppzH)Cl2] (2) were synthesized by reacting CuCl2·2H2O with the monobasic tridentate Schiff-base ligands [Hsal-ppz] (I) and [Hyap-ppz] (II) (derived by reacting 1-(2-aminoethyl) piperazine with salicylaldehyde and 2-hydroxyacetophenone) respectively. Elemental analysis, IR, UV-Vis, 1H NMR and 13C NMR data confirm the structures of the ligands and those of the complexes. Both complexes are monomeric in nature in the solid state and in solution as well. Single crystal XRD data suggest a distorted square pyramidal geometry for 1 crystallized in the P1 space group. DFT studies established a similar molecular structure for 2. The synthesized metal complexes [CuII(sal-ppzH)Cl2] (1) and [CuII(hyap-ppzH)Cl2] (2) successfully catalyzed the oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC) in methanol in the presence of H2O2 with high Kcat values of 1.182 × 104 mmol h-1 and 2.880 × 104 mmol h-1, respectively. [CuII(sal-ppzH)Cl2] (1) and [CuII(hyap-ppzH)Cl2] (2) were also anchored into the polymeric matrix of chloromethylated polystyrene and were analyzed by TGA, atomic absorption spectroscopy (AAS), EPR, scanning electron microscopy (SEM) as well as energy dispersive X-ray (EDX) analysis. The polymer grafted metal complexes were used as catalyst precursors in the oxidative bromination of salicylaldehyde in the presence of H2O2, KBr and HClO4. Under optimized reaction conditions, both catalysts show nearly quantitative oxidative bromination of salicylaldehyde, with the order of % products formed being 5-bromosalicylaldehyde > 3,5-dibromosalicylaldehyde > 3-bromosalicylaldehyde. Plausible reactive species involved in the catalytic cycle are identified by UV-Vis spectroscopy, pH metric titration, ESI-MS, EPR and DFT studies.
- Kumari, Sweta,Mahato, Arun Kumar,Maurya, Abhishek,Singh, Vijay Kumar,Kesharwani, Neha,Kachhap, Payal,Koshevoy, Igor O.,Haldar, Chanchal
-
p. 13625 - 13646
(2017/11/27)
-
- Synthesis, crystal structures and catalytic activity of Cu(II) and Mn(III) Schiff base complexes: Influence of additives on the oxidation catalysis of cyclohexane and 1-phenylehanol
-
The complexes of copper [Cu(κONN’-HL)(NO3)(DMF)](NO3)?H2O (1) and [Cu(κONN’-HL)Cl2]??DMSO (2), and of manganese [Mn(κON-HL)2Cl2]Cl (3) and [Mn(κON-HL)2(NO3)2](NO3)?H2O (4) were synthesized by reactions of the respective chloride or nitrate salt with a non-aqueous solutions of the Schiff base aminoalcohol HL (product of condensation of salicylic aldehyde and aminoethylpiperazine) and characterized by X-ray diffraction analysis. The catalytic investigations disclosed a prominent activity of the copper compounds 1 and 2 towards oxidation of cyclohexane with hydrogen peroxide in the presence of various promoters (nitric, hydrochloric, oxalic acids and pyridine), under mild conditions. The unusual promoting effect of pyridine on the catalytic activity of the copper catalysts allowed to achieve yields up to 21% based on cyclohexane. Chromatographic studies revealed that cyclohexyl hydroperoxide is a main reaction product and chlorocyclohexane (in the presence of HCl as promoter) was also detected, suggesting a free radical reaction pathway with hydroxyl radicals as attacking species. Complexes 1 and 2 act also as catalysts in the oxidation of 1-phenylethanol with tert-butylhydroperoxide, showing acetophenone yields up to 62% and TON (turnover numbers) up to 620 in the presence of the K2CO3 promoter.
- Nesterova, Oksana V.,Nesterov, Dmytro S.,Krogul-Sobczak, Agnieszka,Guedes da Silva, M. Fátima C.,Pombeiro, Armando J.L.
-
p. 506 - 515
(2016/12/16)
-
- Configuration change from cis to trans of isothiocyanato groups in nickel(II) species: Experimental verification and theoretical interpretation of reaction consequence and study on their bio-activity
-
Two new mononuclear Ni(II) complexes, namely [Ni(HL)(SCN)2(H2O)] (1) and [Ni(HL)(SCN)2(4,4′-bipy)] (2) [HL = 2-[(2-piperazin-1-yl-ethylimono)-methyl]phenol] have been synthesized and structurally characterized. The uncoordinated nitrogen atom of the piperazine moiety is protonated to provide electrical neutrality to the system. The configuration of the isothiocyanato ligands is different in the two complexes, cis located in 1 and trans in complex 2. The change of configuration of the isothiocyanato groups on addition of the neutral spacer 4,4-bipyridine to complex 1 has been monitored by conductometric and FTIR spectral studies and the most probable mechanistic pathway has been proposed. DFT calculations have been performed and the outcome corroborates well with the experimental facts. The anticancer activity of the two Ni(II) complexes has been evaluated in human cervical (HeLa) cancer and breast cancer (MCF-7) cell lines. The cytotoxic effects of these complexes were determined by an MTT assay. The fluorescent intensity obtained in HeLa cells reveals the generation of ROS by the complexes using DCFH-DA (2,7-dichlorofluorescein diacetate) dye. The apoptotic cell death was determined by fluorescent staining with acridine orange and ethidium bromide, which confirmed the presence of apoptotic cells. Further, flow cytometry analysis was done, suggesting an arrest of the cell cycle in the S phase of the HeLa cells. Although a detailed molecular mechanism for the anticancer activity of the two complexes was not ascertained, the experimental results suggest that both complexes are effective anticancer agents, with complex 2 seeming to be more promising. The result also indicates that the apoptotic cell death in the cancer cell might be triggered by the process of ROS generation with the complexes. Thermo gravimetric analysis of two complexes hints that NiO particles are the final product after decomposition of the complexes at 600 °C.
- Adhikary, Jaydeep,Chakraborty, Prateeti,Chattopadhyay, Tanmay,Prasad, Ritika,Motro, Yair,Koch, Biplob,Mautner, Franz A.,Miller, Yifat,Das, Debasis
-
-
- Mononuclear zinc(II) complexes of 2-((2-(piperazin-1-yl)ethylimino)methyl)- 4-substituted phenols: Synthesis, structural characterization, DNA binding and cheminuclease activities
-
Four new zinc(II) complexes [Zn(HL1-4)Cl2] (1-4), where HL1-4 = 2-((2-(piperazin-1-yl)ethylimino)methyl)-4-substituted phenols, have been isolated and fully characterized using various spectro-analytical techniques. The X-
- Ravichandran,Gurumoorthy,Karthick,Kalilur Rahiman
-
p. 147 - 157
(2014/03/21)
-
- Magneto-structural correlation, antioxidant, DNA interaction and growth inhibition activities of new chloro-bridged phenolate complexes
-
A new class of chloro-bridged dinuclear nickel(ii) and copper(ii) phenolate complexes (1-8) were synthesized from 4-substituted-2-((2-(piperazin-1-yl)ethylimino)methyl)phenols (L1-4) and characterized. The XRD analysis of complexes 4 and 8 show
- Gurumoorthy, Perumal,Mahendiran, Dharmasivam,Prabhu, Durai,Arulvasu, Chinnasamy,Rahiman, Aziz Kalilur
-
p. 42855 - 42872
(2015/02/19)
-
- Synthesis and antimicrobial screening of 4-thiazolidinone and 2-azetidinone derivatives of piperazine
-
The Schiff's bases 3a-3h were synthesized by reacting substituted/ unsubstituted aromatic aldehydes 2a-2h with 1-(2-aminoethyl)-piperazine 1. A series of novel aryl-3-(2-piperazin-1-ylethyl)-1,3-thiazolidin-4-one 4a-4h and 3-chloro-1-{2-[4-(chloroacetyl)piperazin-1-yl]ethyl}-4-arylazetidin-2-one 5a-5h were synthesized from the Schiff's bases of 1-(2-aminoethyl)-piperazine 3a-3h. The structures of synthesized compounds were confirmed by analytical (C, H, and N) and spectral (FT-IR, 1H NMR, 13C NMR, and Mass) data. The compounds 4a-4h and 5a-5h were screened for antimicrobial activity. The compounds 4a, 4d, 4f, 4g, 5a, 5d, 5f, and 5g exhibited substantially significant antibacterial as well as antifungal activity.
- Shingade, Sunil G.,Bari, Sanjaykumar B.
-
p. 699 - 706
(2013/04/10)
-
- A series of mononuclear nickel(II) complexes of Schiff-base ligands having N,N,O- and N,N,N-donor sites: Syntheses, crystal structures, solid state thermal property and catecholase-like activity
-
Four new mononuclear nickel(II) complexes, namely [NiL1(H 2O)3](NO3)2 (1), [NiL 2(H2O)3](NO3)2 (2), [NiL3(H2O)3]
- Guha, Averi,Banu, Kazi Sabnam,Das, Sudhanshu,Chattopadhyay, Tanmay,Sanyal, Ria,Zangrando, Ennio,Das, Debasis
-
p. 669 - 678
(2013/06/05)
-
- AMINOMETHYLATION OF N-(β-AMINOETHYL)PIPERAZINE AND ITS DERIVATIVES
-
The aminomethylation of N-(β-aminoethyl)piperazine and its derivatives - N-piperazine, N-ethylpiperazinophthalimides, N-(β-salicyclideneaminoethyl)piperazine - results in the formation of polyfunctional compounds.The reacti
- Zagidullin, R. N.
-
p. 225 - 230
(2007/10/02)
-